A blood test is a laboratory analysis performed on a blood sample that is usually extracted from a vein in the arm using a needle, or via fingerprick. Multiple tests for specific blood components (such as a glucose test or a cholesterol test) are often grouped together into one test panel called a blood panel or blood work.
Upper Air Troughs. When the height contours bend strongly to the south, (as in the diagram below), it is called a TROUGH. Strong troughs are typically preceded by stormy weather and colder air at the surface. Here is an example of a trough in an upper-level height field (red contours).
From your trachea, air splits off into your right and left main bronchial tubes, or right and left main bronchus. As your bronchial tubes continue to branch off and get smaller and smaller, they are referred to as bronchi and then bronchioles. Your airways terminate at the air sacs called alveoli, where the exchange of carbon dioxide and oxygen takes place. The alveoli are surrounded by a network of blood vessels called capillaries.